Water jet tools producing high-pressure jets of water containing abrasive particles are used to cut a variety of materials including metals, stone, ceramics, concrete, tile and glass. A water jet tool connects a high-pressure fluid pump to a cutting head in order to produce an ultra-high-pressure water jet for discharge through a water jet nozzle. Before the water jet is discharged, an abrasive particulate, such as garnet particles, is added to facilitate the cutting of the material. The water containing the abrasive particulate is ejected through the water jet nozzle at a rate of approximately 1 gallon per minute (GPM) onto a workpiece that is restrained on a cutting table. As the water jet containing the abrasive particulate passes through the workpiece, it is collected in a catch tank below. This 1 GPM of heavily contaminated water flows out of the catch tank by gravity into a drain or preferably into a recycling system. Due to the abrasive character of the particulate, the fluid and particulate slurry are abrasive and damaging to the particulate recycling system. In particular, the pump used to draw the particulate slurry through the filtration system is subject to frequent breakdown and to damage caused by the particulate, and this heavy particulate slurry causes frequent filter replacement. A review of prior art particulate filtration systems for use with water jet cutting tools demonstrates this point.
Settling tanks are implemented to collect the particulate matter by means of directing the slurry discharge through a tank having a large volume with an input and an output near the upper portion of the tank. The slurry is pumped into the settling tank, where the volume of the fluid contained therein reduces the flow and turbulence within the tank, allowing the heavier particulate matter to settle towards the bottom and the fluid to flow out through a discharge.
The drawback to this type of system is the need to frequently shut down the system in order to clean out the particulates which have collected in the bottom. This process requires a significant amount of time in which the system is not running, while the maintenance is performed, as well as a significant amount of burdensome cleansing of the settling tank.
Therefore, there is a need for a cost-effective settling/filtration system that will not require shutting down the system for lengthy periods of time in order to clean out the settling tank, increasing the overall efficiency of the process.